I pre-cut the cork in a long strip to the correct width for the key and apply a thin layer of contact cement to the cork and the key. I wipe the sides of the key immediately if the cement spills over to that area. When dry, I attach the cork and simply trim to length. The sides look just fine.

John

 

Cutting the corks is simply a knack, you seem to be covering most of it correctly. Sharp blade is essential, when you slice the edge of the cork, dont make the edge of the cork a straight cut, bevel it more to the 45 degrees inwards, minimise contact cork area as well.

Quality of the cork counts as well, cheap craft cork doesnt feather as nicely.

If you want even smoother edges and you have nickel plated keys you can then use some 600 sandpaper and gently sand the edges smooth.

 

Cutting the corks is simply a knack, you seem to be covering most of it correctly. Sharp blade is essential, when you slice the edge of the cork, dont make the edge of the cork a straight cut, bevel it more to the 45 degrees inwards, minimise contact cork area as well.

On the foot of a clarinet key cutting the cork to an inward bevel of 45 degrees would leave only a thin point of contact with the body of the clarinet. This is not a good idea in my opinion. The cork is better left square or nearly square to maximize the contact area to reduce compressing the cork as you play and opening the keys farther than necessary.

Realistically, if the cork is trimmed with a sharp blade so that it doesn't have the amateurish "saw blade teeth" pattern on the edge, does it much matter how perfect it looks close up? No player is going to notice or care if there is a miniscule line of cement between the cork and the key. There are many other truly important details in clarinet repair that are more deserving of a tech's time and energy than this one IMNSHO.

John

 

When I finish trimming the corks, I wipe the fuzzy edges caused by the contact cement with paint thinner. Works like a charm.

 

You can try what the lady in the Buffet clip does

(5:30-5:40)

I use a razor. I tried all sorts of knifes but nothing seems sharp enough. If it's very sharp it looks good. If there are "tails" just cut them off. Remove extra contact glue with your finger after smearing on the key (before it dries). After it's dry and you cut you can try removing any extra with your fingers too. Sismo's suggested to cut at an angle can be good sometimes but be careful if the cork is very narrow, so you don't get too thin cork which would be more squishy and maybe without enough support.

By the way, are you talking specifically about natural cork? I rarely use that for keys (except some specific places sometimes).

 

Thanks for the replies guys.

It seems there's nothing wrong with my work practices, as I already do all of the above.

Clarnibass, yes it's natural sheet cork from music medic. The quality of sheet cork seems to have dropped off markedly. I've never used the tech cork but I'm open to suggestions.

 

Clarnibass, yes it's natural sheet cork from music medic. The quality of sheet cork seems to have dropped off markedly. I've never used the tech cork but I'm open to suggestions.

Yes, I recommend you try other materials. Other than tenons and sax necks, I use natrual cork sometimes (but not much) in specific places on saxophones, but I don't remember that I use it at all anymore on clarinets.

I think the two materials I use the most are rubber-cork (which is the same as tech-cork from Music Medic) and synthetic felt (occasionally in combination with another material for example teflon, or another). Depending on the place, I would choose one of these.

The tech-cork is much harder to sand than regualr cork, but it is much better for some situations (like John explained). Although it is harder to sand, it is very easy to sand with an appropriate bit on the micromotor.... However aligning keys by sanding cork is ok but most of the time a much slower and less accurate method anyway (though sometimes necessary).....

I don't see Music Medic stocks the synthetic felt, but you can get it for example from www.windcraft.co.uk It is always a compromise between accuracy and noise but some materials are better and this synthetic felt is very firm and accurate considering it is also very quiet.

I haven't yet seen the synthetic felt on any instrument but companies like Yanagisawa, Yamaha, Borgani are using the tech-cork material for a while now.

 

D.P. The tech cork is an amazing material. I use it exclusively for key feet and linkages due to its ability to hold its shape and not compress. Yamaha now uses it on all of their reed woodwinds. The other great thing is that it is available in so many thicknesses that there is rarely a need to sand to get the right dimension. Curt sells an assortment that is an ideal way to try it out.

In terms of gluing and cutting, it is about the same as natural cork. It is a bit harder to sand, however but as I said with so many thicknesses available sanding is rarely necessary.

John

 

I use razor blades, but to apply the contact cement I use old reeds which helps me apply just the right amount. its also great for clarinet tenons - just cut the reed to the right width, apply a small amount of glue to the reed and place the clarinet on a bench peg put the reed on the tenon and rotate the clarinet.

 

As others have said, except:

Unlike JBT, I trim sides and both ends of the cork after gluing onto the key.

Unlike Simso, I cut the cork at right angles along the sides of the key stop. I angle the cut at the ends only.

I do not use razor blades. A bit fiddly for me. I use a Tajima LC-303 snap-blade knife - the one with the coloured easy-to-locate-on-the-bench handle. ttp://www.tajimatool.com/products/snapblade/precision_craft/view.php?page=all
I use it with the blade well out from the handle. That enables a long, slicing "stroke". I re-sharpen a blade a few times with a diamond hone before replacing it. The cheap, Chinese replacement blades are disappointing; I buy genuine.

Nothing is better than a finger for spreading contact cement. The surplus on the finger can be easily rubbed off in the palm of the other hand.

Dogpants, rise above Selmer's low standards; up your own... get the superior materials!

 

A magnifying glass reveals that the fuzziness isn't cork but the thin layer of contact cement between the key and the cork, that is not cutting cleanly.

Try a different glue.
It seems to me that if you are using your fingers then the glue is to thick.

 

It seems to me that if you are using your fingers then the glue is to thick.

I've tried not using my finger. IME using my finger actually has the most control of exactly how thick/thin I want it. It's also the most even. Using a brush or something like that has less control and is less even.

 

I stick the cork on with contact cement and then use the key to press the cork down on top of a piece of very thick leather. That lets the Exacto knife blade cut through the cork and into the leather, giving a cleaner cut and not dulling the tip of the blade. I usually cut at 90 degrees on thin stuff and only use the blade to bevel a cut on really thick stuff (to save me time when later shaping the cork). Then, I use a fine emery board to put on a bevel. The angle isn't so important as getting rid of the sharp edge, which can catch on things, like a cloth when cleaning the horn. The thicker the cork, the more the rounding off.

The emery board is silent on the cork. When you hear a scritch, that means metal and you're going to far. Right before you hit metal, the emery board will usually roll up a tiny "booger" (that's the technical term) of contact cement that can be picked off. That's my signal to stop before the metal.

I've also replaced cork in situ. For this, you need to be 1) very careful and 2) very lazy. I put at least five layers of Post-It Note (only the stickum part) under the key with the stickum side stuck to the horn. That keeps the paper from shifting. Sometimes I use an old reed to apply the cement, sometimes I set the key down on the already cemented cork, then lift the key and let the glue on the key and cork dry a little. I then set the cork and trim with a really sharp Exacto. Even with a large selection of different shaped Exacto blades, it's usually not perfect, but it's fast when there is only one problem cork on the whole stack. Like the leather, the paper tends to produce a nice cut edge.

Mark

 

It must be a thicker glue then I use.
It seems messy to use your finger.
It is would be if I used mine.

 

It must be a thicker glue then I use.
It seems messy to use your finger.

Maybe it is messy to use your finger... but it is not messy when I use my finger....

What I do is "squish" a tiny bit (exact amount I want) from the small nozzle on the key or cork (or sometimes on my finger). Then smear it. Smearing with a finger is more even and allows better control of thickness IME. If extra is sliding to the sides of the key, I wipe it also with a finger (when it's still not dry, you can control if you want to smear or remove by how hard you press).

I know some repairers use a brush to smear, and sometimes with contact glue from a can. I tried this, and for me it is far less comfortable.

Gordon, Evostik is thin compared with itself. I would say it's average compared with all contact glues I've tried. I've tried a few that were thinner. I dismissed those, partly (but not only) because of that (especaily if the nozzle hole is not very small it is worse).

 

I use double edge razor blades.I use a lot of them. a new blade cuts great. I buy the house brand because they are cheaper. The double edge blades are thin and they cut better. Sometime I break them in half and use them that way. I also
break them at a angle and make them pointed.I also glue one to a ice cream bar stick and cut corks off keys while they are still on the horn.

 

I know this is a very old post but I just came upon it and wanted to +1 on how great the double edge blades work. Like Ken K I break them in half, and sometimes use metal snips to cut them into an angle on one end to make more of a point for tight places. They also work like a super-sharp exacto knife when glued to a popsicle stick, making it much easier to cut corks very cleanly while on the horn.

 

You could also, if you dont want to use contact cement. "Which I do use", use georges glue, it allows you to heat the key and move the cork into the exact postion you want it to be.

Regarding the trimming of corks, I apologise on the misunderstanding, the bottom keys of a clarinet B,C,C#,Eb etc I cut the cork at a 45 degree, so its bevelled inwards, this also applies to large contact areas such as register key, bridge keys and so forth.

For trills and small contact keys I cut the edges along the key at a 90 degree straight edge, but on the length ways (underside) of the keys the ends are cut at a 45.

Another good option is to get some hole punches and punch out various size circles which you can glue into place, so for example low C# instead of corking the whole underside of the key, you could use a singular circle at the touch point.

Practice, practice and more practice, sounds like your doing fine any way

As nitai pointed out, I use my finger to smear as well, however my contact cement is in a can, and I brush it on first with a paint brush and then smear smooth

 

My contact cement (S-18) comes with a thinner.
I woulden't be able to do that if it came in a tube.

 

I try not to get any glues containing solvents on my skin, for the same reason that I don't want to breath them. Your skin is a permiable membrane, just like your lungs. Methyl ethyl ketone, the common solvent in contact cement can pass through both membranes causing both short term and long term systemic neurologic problems. Your lungs are very efficient at transmitting airborne chemicals. Passing MEK through your skin only becomes an issue if there is direct contact, i.e., you get the crap on you.

I represented a small boat building business whose principals were alway fighting with each other, with the landlord, with the police, whatever. I thought that they were all paranoid. I believe it was because they breathed styrene gas from polyester resins, cleaned parts with MEK, washed their hands with acetone, etc. The were "mad as hatters" and for a similar reason.

Mark

 

Neuro damage with MEK? That is, apparently, news to the medical community:

http://www.epa.gov/ttn/atw/hlthef/methylet.html

I agree that it is best to get as little dermal and respiratory exposure to most solvents as possible, but it is quite easy to look up the toxicity of various chems on the 'net.

Toby

Toby

 

Over 45 years of buying and using mine (in tubes), I have never needed to thin it. So no need for a thinner.

If you buy a can, and keep tking the lid off, exposing a large surface to the atmosphere, yes, of course you will need a thinner.

In the nozzle of my tube I jam a short length of teflon tube, 1 mm diameter ID. So only about a square mm of suface is ever exposed to the atmosphere. I don't ever cap that tube. No need.

 

MEK + cigarette smoke = phosphene gas
(world war1 poison gas)

 

Moral: Don't smoke!

 

I buy nail polish bottles from Rachel's Supply and mix my contact cement about 50:50 with thinner (I have generally used the cement from Ferrees). The brush built in to the cap allows me to precisely make a very thin coat, and the thin glue dries quite fast, keeping it off my fingers.

 

"I also agree that contact cement is very toxic"

And AFAIK antiperspirant is a lot worse.

Whether glue solvents penetrate a tradesman's thick, dry, finger skin, and get into the bloodstream is highly questionable. Especially considering that these solvent nasties also evaporate very fast, almost certainlyi before they get deep enough into the skin to meet blood.

It would be far worse to breathe some lead or toluene-laden petrol fumes while filling the car. Straight to the lungs for absorption!

Wiping with a finger has a big advantage over brush. I can apply enough pressure during the first wipe (or 2) to push that glue into the micro-rough surface of the metal. Then with another wipe following immediately, I can fully control just how thick the glue will be. And for me, that is a lot thinner than what you would achieve by brushing (unless you diluted your glue to as thin as water).

Hence the cork can be applied within a minute.

Thicker glue makes the joint weaker rather than stronger.

 

Whether glue solvents penetrate a tradesman's thick, dry, finger skin, and get into the bloodstream is highly questionable. Especially considering that these solvent nasties also evaporate very fast, almost certainlyi before they get deep enough into the skin to meet blood.

It would be far worse to breathe some lead or toluene-laden petrol fumes while filling the car. Straight to the lungs for absorption!

It's a matter of cumulative exposure. I know of a case involving someone who painted miniatures for a living, and the xylene/toluene absorbed through the skin was eventually enough to lead to liver failure and death, and pretty obvious neurological effects toward the end. It took 20 years of "it will never hurt me" bad practices, but it does happen. He would wash with paint thinner at the end of the day to get the paint off his hands, so it's not at all the same as wiping contact glue with a fingertip, but at some level it becomes significant.

 

Medical supply. Scalpels.

 

I use one of these, and re-sharpen the blade several times before replacing.

http://www.preservationequipment.com/UserData/root/Products/Images/000567_0.jpg.thumb?w=283&h=283

 

Everyones different, some people from a single exposure will have adverse reactions and others wont get any in there whole lifetime, most painters that I know have dry skin because of the exact problem above, as in they wash there hands at the end of the day with paint thinners.

As far as wine damaging the liver, thats a risk Im willing to take

 

These are the bomb, much more precise, and you can get in anywhere.
http://www.tedpella.com/dissect_html/scalpel.htm#anchor_disp_scalpels

 

They may well be the bomb,and I've tried them.

But IMO cork is best with a slicing action. For that, you need length of blade.

Also scalpel blades blunt very quickly. AFAIK they are designed for single-use on flesh, not multiple use rubbing against metal.

But I do use a scalpel with #11 blade for inaccessible places while a key is mounted, on rare occasions.